Heartbeat message ensures the connectivity between _____ and ____*1 pointNameNode and DataNodeNameNode and Node ManagerDataNode and Resource ManagerNone

The heartbeat message ensures the connectivity between NameNode and DataNode.

Here's a step-by-step explanation:

1. In Hadoop, the NameNode is the master node that manages the file system metadata and controls access to files by clients.

2. The DataNode is a slave node that stores the actual data in HDFS (Hadoop Distributed File System).

3. The heartbeat is a signal used in computer networks to indicate the normal running status of a node or a connection.

4. In the context of Hadoop, the DataNode sends a heartbeat message to the NameNode every few seconds to signify that it is functioning correctly and the connection is alive.

5. If the NameNode does not receive a heartbeat from a DataNode within a specified amount of time, it assumes the DataNode has crashed or has network connectivity issues.

6. Therefore, the heartbeat message ensures the connectivity between NameNode and DataNode.